Diagnostic performance of triple-contrast versus single-contrast multi-detector computed tomography for the evaluation of penetrating bowel injury

PURPOSE

Selecting groups of low-risk penetrating trauma patients to forego laparotomy can be challenging. The presence of bowel injury may prevent non-operative management. Optimal CT technique to detect bowel injury related to penetrating injury is controversial. Our goal is to compare the diagnostic performance of triple-contrast (oral, rectal, and IV) against IV contrast-only CT, for the detection of bowel injury from penetrating abdominopelvic trauma, using surgical diagnosis as the reference standard.

METHODS

Nine hundred ninety-seven patients who underwent CT for penetrating torso trauma at a single institution between 2009 and 2016 in our HIPPA-compliant and institutional review board-approved retrospective cohort study. A total of 143 patients, including 15 females and 123 males underwent a pre-operative CT, followed by exploratory laparotomy. Of these, 56 patients received triple-contrast CT. CT examinations were independently reviewed by two radiologists, blinded to surgical outcome and clinical presentation. Results were stratified by contrast type and injury mechanism and were compared based upon diagnostic performance indicators of sensitivity, specificity, negative predictive value, and positive predictive value. Area under the receiving operating characteristics curves were analyzed for determination of diagnostic accuracy.

RESULTS

Bowel injury was present in 45 out of 143 patients (10 on triple-contrast group and 35 on IV contrast-only group). Specificity and accuracy were higher with triple-contrast CT (98% specific, 97-99% accurate) compared to IV contrast-only CT (66% specific, 78-79% accurate). Sensitivity was highest with IV contrast-only CT (91% sensitive) compared with triple-contrast CT (75% sensitive), although this difference was not statistically significant. Triple-contrast technique increased diagnostic accuracy for both radiologists regardless of mechanism of injury.

CONCLUSION

In our retrospective single-institution cohort study, triple-contrast MDCT had greater accuracy, specificity, and positive predictive values when compared to IV contrast-only CT in evaluating for bowel injury from penetrating wounds.

Hydrogel-based 3D bioprints repair rat small intestine injuries and integrate into native intestinal tissue

3D Printing has become a mainstay of industry, with several applications in the medical field. One area that could benefit from 3D printing is intestinal failure due to injury or genetic malformations. We bioprinted cylindrical tubes from rat vascular cells that were sized to form biopatches. 2 mm enterotomies were made in the small intestine of male Sprague-Dawley rats, and sealed with biopatches. These intestinal segments were connected to an ex vivo perfusion device that provided independent extraluminal and intraluminal perfusion. The fluorescence signal of fluorescein isothiocyanate (FITC)-inulin in the intraluminal perfusate, a non-absorbable fluorescent marker of intestinal integrity, was measured every 15 min over 90 min, and used to assess the integrity of the segments under both continuous perfusion and alternate-flow perfusion. Enterotomies were made an inch away from the ileocecal junction in male Wistar rats and sealed with biopatches. The animals were monitored daily and euthanized at post-operative days 7, 14, 21, and 30. Blinded histopathological analysis was conducted to compare the patch segments to native intestine. Biopatch-sealed intestinal segments withstood both continuous and pulsatile flow rates without leakage of FITC-inulin above the control baseline. 21 of 26 animals survived with normal activity, weight gain, and stool output. Histopathology of the explanted segments showed progressive villi and crypt formation over the enterotomies, with complete restoration of the epithelium by 30 days. This study presents a novel application of 3D bioprinting to develop a universal repair patch that can seal lesions in vivo, and fully integrate into the native intestine.

Blunt Isolated Small Bowel Perforation Intervention: Does a Delay in Management Matter?

Purpose

Blunt small bowel injury is rare, and its timely diagnosis may be difficult. The effects of a delayed intervention on prognosis are unclear. We aimed to determine whether the time to surgical intervention affects outcomes in patients with blunt small bowel perforation.

Methods

The study was performed between March 2010 and December 2018 in adults (age >18 years) who initially underwent computed tomography and small bowel surgery only and survived more than one day postoperatively. They were categorized into three groups based on injury-to-surgery time intervals: ≤8, 8-24, and >24 h; similarly, they were also categorized into two groups of ≤24 and >24 h.

Results

Bowel resection, length of stay (LOS), intensive care unit (ICU) LOS, morbidity, and mortality were analyzed as outcomes in 52 patients. The number of patients in the three groups (≤8, 8-24, and >24 h) based on the time-to-surgery was 33, 13, and 6, respectively. On comparing the three groups, there were no significant differences in LOS (24 [18-35], 21 [10-40], and 28 [20-98] days, respectively; p=0.321), ICU LOS (2 [1-12], 4 [2-26], and 11 [7-14] days; respectively, p=0.153), mortality (3% (n = 1), 15% (n = 2), and 0%, respectively; p=0.291), and morbidity (46% (n = 15), 39% (n = 5), and 50% (n = 3), respectively; p=0.871). However, there was a significant difference between the groups in bowel resection (67% (n = 22), 31% (n = 4), and 83% (n = 5), respectively; p=0.037). Additionally, there was no significant difference in outcomes between the two groups (≤24 and >24 h) with small bowel perforation.

Conclusions

Delay in surgical intervention following blunt abdominal trauma may not affect the outcomes of patients with small bowel injuries, such as LOS, ICU LOS, morbidity, and mortality, except bowel resection.

Characteristics of Combat-Associated Small Bowel Injuries

INTRODUCTION

Although there are multiple studies regarding the management and outcomes of colonic injuries incurred in combat, the literature is limited with regard to small bowel injuries. This study seeks to provide the largest reported review of the characteristics of combat-associated small bowel injuries.

MATERIALS AND METHODS

The Department of Defense Trauma Registry was queried for U.S. Armed Forces members who sustained hollow viscus injuries in the years 2007-2012 during Operations Enduring Freedom, Iraqi Freedom, and New Dawn. Concomitant injuries, procedures, and complications were delineated. Fisher's exact test was used to analyze the relationship of bowel injury pattern to rates of repeat laparotomy, fecal diversion, and complications.

RESULTS

One hundred seventy-one service members had small bowel injuries. The mean age was 25.8 ± 6.6 yr with a mean injury severity score of 27.9 ± 12.4. The majority of injuries were penetrating (94.2%, n = 161) as a result of explosive devices (61.4%, n = 105). The median blood transfusion requirement in the first 24 h was 6.0 units (interquartile range 1.0-17.3 units). The most frequent concomitant injuries were large bowel (64.3%, n = 110), pelvic fracture (35.7%, n = 61), and perineal (26.3%, n = 45). Fifty patients (29.2%) had a colostomy, and nine patients (5.3%) had an ileostomy; 62.6% (n = 107) of soldiers underwent more than one laparotomy. The mortality rate was 1.8% (n = 3). The most common complications were pneumonia (15.2%, n = 26), deep vein thrombosis (14.6%, n = 25), and wound infection (14.6%, n = 25). The need for repeat laparotomy and fecal diversion was found to be significantly associated with injury pattern (p = 0.00052 and p < 0.0001, respectively).

CONCLUSION

We found that two-thirds of service members with small bowel injuries also had a large bowel injury. One-third of the patients required diversion and two-thirds had more than one laparotomy. The pattern of bowel injury significantly affected the need for repeat laparotomy and fecal diversion.

Isolated complete jejunal transection following abdominal blunt trauma with delayed presentation

In blunt trauma, diagnosis of small bowel injury is infrequent and accounts for less than 1.1% of blunt trauma admissions. Of those, only 0.3% are perforated.¹ Isolated transection of the jejunum following blunt abdominal trauma has rarely been reported in literature.^2,3 Most cases of small bowel perforations after blunt trauma occur as a result of motor vehicle crashes and falls from heights and are often associated with multiple injuries.⁴ This is a report of a 26 year-old female that presented 14 h after being involved in a motor vehicle crash and was found to have complete transection of her proximal jejunum with underlying mesenteric injury. Following the crash, the patient extricated herself from the vehicle, went home, and fell asleep with no significant complaints initially reported. She woke up hours later with severe abdominal pain and presented to our emergency department. CT was performed and revealed free fluid in the abdomen. Subsequently, an exploratory laparotomy was performed that revealed complete jejunal transection with underlying mesenteric injury. Isolated complete transection of the proximal jejunum should be considered in the evaluation of patients following blunt abdominal trauma, and presentation may be delayed up to 14 h. To the best of our knowledge, this is the first case report of complete transection of the proximal small bowel following a motor vehicle crash with the longest delay in presentation reported in the literature.